1. Field of the Invention
This invention pertains to blow guns for cleaning work pieces.
2. Description of the Prior Art
A conventional, manually operated, blow gun may have a handle with an inlet adapted to be connected to a source of compressed air and an outlet which may include a nozzle. Frequently associated with the nozzle are aspirating devices wherein outside air is combined with source air for economical flow. Also included may be nozzle structure to produce an air cone to protect the blow gun operator from flying chips or particles. The control for the blow guns is usually a trigger operated, poppet valve which connects the nozzle to the air inlet when the trigger is depressed and disconnects same, via biasing means, when the trigger is released.
Recent U.S. Government (O.S.H.A.) safety standards specify that compressed air cannot be used for cleaning purposes except when reduced to 30 p.s.i. or less, and then only with effective chip guarding. The above standard has also been interpreted by the O.S.H.A. Administration to permit use of a nozzle for cleaning operations which includes a pressure reducer or a device which will reduce air pressure to 30 p.s.i. or less if the nozzle is dead ended.
To meet the above standard, most manufacturers have merely built in either pressure reducers or regulators which only allow 30 p.s.i. at the nozzle continuously. Inasmuch as the usual pressure available at the nozzle has been 100 p.s.i., the air pressure available for cleaning is severely reduced and the effectiveness of the blow gun is diminished.